Most people who use cordless telephones are familiar with the need to recharge the battery contained within the handset. A visual inspection of most cordless telephone handsets usually reveals the presence of electrical contacts embedded in the handset. When the handset is placed into the base of a cordless telephone, the contacts form a circuit with matching contacts embedded in the base. This circuit connection is used to recharge the battery contained in the handset using a power source routed through the base. These contacts are referred to as xe2x80x9ccradle contacts.xe2x80x9d The recharging of the handset necessarily requires an electrical current, referred to as a charging signal, to flow through the matching contacts.
During the manufacturing process both the base and handset must be tested to insure they are working properly. Additionally, handsets/bases must be tested when they are returned for servicing. Typically, once a handset has been assembled it can only be tested by removing its cover in order to access internal circuitry or by removing the battery from the battery compartment. Either way, the handset is tested by connecting a test fixture to the handset using an xe2x80x9cinternalxe2x80x9d (i.e., not on the surface of the handset) connection. The handset may include an internal, dedicated connector called a Test Access Port (xe2x80x9cTAPxe2x80x9d). Once a connection has been established with a test fixture using a TAP or the like, the test fixture may send diagnostic message signals over the connection to internal processors or the like located inside the handset, e.g., digital signal processors, in order to conduct diagnostic tests.
Using internal TAPs to complete diagnostic tests is time-consuming because it requires that the handset (or base) be partially disassembled (i.e., to fix it) or partially assembled (i.e., when it is being made) to conduct the tests. Some cordless telephones have sought to solve this problem by placing the TAPs on the external surface of the handset (or base). While this may reduce the time it takes to complete the diagnostic tests, it has its drawbacks. First, placing TAPs on an external surface exposes them to a user. The risk is that the electrical contacts making up the TAPs could be damaged and rendered useless. Second, exposing TAPs results in a degradation in their conductivity over time.
Some have tried to use an RF link in order to carry out diagnostic tests. However, the production/manufacturing environment can be a harsh, frequency environment containing severe RF interference making the use of RF links impractical.
There is a need, therefore, for an improved means of completing diagnostic tests of a handset or base of a cordless telephone using a complementary test fixture/set-up.
Accordingly, it is an object of the present invention to provide for systems and methods for completing diagnostic tests of a handset or base of a rechargeable device without using internal TAPs.
Other objectives, features and advantages of the present invention will become apparent to those skilled in the art from the following description taken in conjunction with the accompanying drawings.
In accordance with the present invention there are provided systems and methods for completing diagnostic tests on rechargeable devices, such as a cordless telephone, using cradle contacts of a cordless handset or base. Using cradle contacts to complete diagnostic tests alleviates the problems associated with the cumbersome use of TAPS because the cradle contacts are located at or near the external surface of a cordless telephone handset or base.
An illustrative embodiment comprises a system which itself may comprise one or more devices such as a test fixture, cordless handset and/or cordless base. Each of these components in turn comprises cradle contacts for inputting and outputting diagnostic messages and a processor for controlling the generation, output and/or input of the diagnostic messages. The processor may comprise a digital signal processor, microprocessor or the like.
The cradle contacts of the test fixture, handset or base may alternatively comprise inductive cradle contacts while the diagnostic message signals may comprise signals not normally present during normal cradle charging, such as ASK message signals. These message signals have different frequencies than traditional charging signals. Embedded in the diagnostic message signals may be additional data which is used to insure the message signals are transmitted/received correctly, such as error checking and framing information.
In addition to cradle contacts and a processor, the test fixture, handset and/or base may also comprise a detector for separately detecting the diagnostic message signals from charging signals. This insures the two will not be confused by the processor.
In order to mark the beginning and end of a diagnostic test, the message signals may further comprise a first code or codes for indicating the beginning of a diagnostic test and/or a second code or codes for indicating the end of a diagnostic test.
The present invention and its advantages can be best understood with reference to the drawings, detailed description of the invention and claims that follow.